This works, I do it all the time.
Use small diameter clear Neoprene tubing on the engine nipple. Connect this to a 3/32" brass tube which is telescoped into a 1/8" brass tube and soldered. This whole device is attached to the model permanently. The fuel bladder tube is then attached to the 1/8" brass tube.
This system allows faster refueling and the tube NEVER blows off the engine.
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Whoops! I misunderstood the question. You're interested in the PRESSURE nipple, not the FUEL nipple. Ho hum, the advice stands. Forget the pressure nipple and run with a bladder.